1. Field of the Invention
In passenger-carrying vehicles, particularly aircraft, it is common to provide seats of different widths for passengers travelling on different classes of fare. For example, a seat provided for passengers travelling "First Class" is usually wider (and designed to provide greater comfort) than a seat provided for passengers travelling on the "Tourist Class" fare. Seats of different widths are also desirable to provide improved comfort for different sizes of passenger.
Vehicles are commonly used to transport passengers travelling on different classes of fare. The numbers of passengers travelling on the different classes is likely to vary form one journey to another. It is therefore a common practice to provide an adjustable seating unit comprising at least one backrest part and at least one bottom part for a plurality of seats abreast, fixed armrests at the sides of the unit and laterally-movable intermediate armrests defining and separating the seats. The intermediate armrests are movable laterally so that the width of the seats can be adjusted, for example between journeys, to accommodate passengers in different fare classes. This invention concerns armrest arrangements for adjustable seating units of this kind for use in passenger-carrying vehicles, which will for convenience be referred to as "adjustable seating units of the kind described".
In its simplest form, an adjustable seating unit of the kind described comprises a backrest part and a bottom part for two seats abreast, with a fixed armrest at each side and two intermediate armrests, each seat being defined by an intermediate armrest and the adjacent fixed armrest and the two seats being separated by the two intermediate armrests. Each intermediate armrest can be moved laterally between two or more predetermined positions to define seats of different widths.
Typically, a "First Class" seat for an aircraft has an overall width up to about one-and-a-half times the width of a "Tourist Class" seat. It is therefore convenient to make an adjustable seating unit of the kind described of overall width sufficient to provide a row of three seats abreast for "Tourist Class" passengers. Such a unit can be adjusted readily to provide two wider seats abreast for "First Class" passengers. Two intermediate armrests are provided, each of which can be located in two alternative laterally-spaced positions. In the first position, all four armrests are equally spaced, defining seats for three "Tourist Class" passengers. In the second position, the two intermediate armrests are each located closer to the centre of the row so as to define with the fixed armrests two wider seats for "First Class" passengers.
2. Description of the Related Art
U.S. Pat. No. 3,145,052 discloses one arrangement (believed to be the first) of an adjustable seating unit as described in the previous paragraph. Each intermediate armrest is supported by a tubular strut which can be inserted selectively into either of two laterally-spaced sockets in the alternative positions. A removable table is provided to bridge the intermediate armrests when they are in the two-seat configuration. A disadvantage of this arrangement is that the intermediate armrests and/or the removable table can readily be removed from the unit and may be lost.
U.S. Pat. No. 4,768,832 discloses an adjustable seating unit of the kind described in which each intermediate armrest is anchored to a fixed part of the seating unit by a linkage and complementary components are provided on the intermediate armrests and the seating unit for selective engagement to locate the intermediate armrests positively in their respective positions. This avoids loss of the intermediate armrests.
An adjustable seating unit of the kind described, of overall width sufficient to provide a row of three seats abreast and adjustable to provide two wider seats, is disclosed in a document of Trans-Australia Airlines dated Sept. 3, 1979 and entitled "B727-276--Passenger Tables". Inter alia, the document discloses a separate wide armcap to fit over the two intermediate armrests when they are positioned close together in the two-seat configuration. When the unit is in the three-seat configuration, the wide armcap is stored in a pocket under one of the seats. It seems that fitting of the wide armcap to the intermediate armrests would be a two-handed operation since the document instructs that this operation should be performed "holding the edges apart". As the wide armcap is a separate component, it could easily be misplaced, lost or damaged.
U.S. Pat. No. 4,533,175 discloses another adjustable seating unit which provides either two wider seats or three narrower seats abreast. There are fixed armrests at the sides of the unit and intermediate armrests are provided which are movable between two positions. In the three-seat configuration the intermediate armrests project vertically out of the lower seat cushion to define and separate three seats of equal width. In the two-seat configuration the intermediate armrests are pivoted down to overlie the centre seat position in a generally ineffective horizontal fashion and the centre part of the back cushion is swung down to form an alternative wider armrest and/or cocktail table to separate and define the two wider seats.